Pulled the head earlier today and found pitting on the #6 piston. One decent ding at the edge of the piston. Pic with red straw shows the location. Straw is 2mm in diameter for scale. Was hoping to get feed back on whether or not this piston needs to come out. Also included is a photo of the #6 spark plug. Specifically there appears to be no insulation left. Was it incinerated? Thoughts on next steps appreciated.